Method for forming resilient plastic seat elements



Se t. 6, 1966 J. J. LEVENSON 3,270,393

METHOD FOR FORMING RESILIENT PLASTIC SEAT ELEMENTS Original Filed Dec. 15, 1962 2 Sheets-Sheet 1 INVFTNTUR.

ATTORNEY Sept. 6, 1966 J. J. LEVENSON 3, 7 ,3

METHOD FOR FORMING RESILIENT PLASTIC SEAT ELEMENTS Original Filed Dec. 13, 1962 2 Sheets-Sheet 2 INVFNTOR d/ JAez/ensm United States Patent This invention relates to spring elements for upholstery purposes and more particularly to an extruded plastic spring element [for use with the usual padding and trim material in a seating unit.

This invention is a division of my co-pending application Serial No. 244,475 entitled, Resilient Plastic Seat Elements, filed December 13, 1962, now Patent No. 3,222,698 granted December 14, 1965.

The conventional seat construction utilizes a multiplicity of spring elements which are hand assembled on a seat frame. Padding and trim materials are placed over the spring elements to complete the seat assembly.

The present invention uses a plastic extrusion in place of the multiple seat springs and will provide a controlled seat contour that is easier and less expensive to assemble.

An object of this invention is to provide a single unitary plastics support element to replace the conventional multiple springs used in seat construction.

A further object of this invention is to provide an extruded spring element which will be less expensive to manufacture and assemble.

Another object of this invention is to provide spring elements which will be more accurately formed thus reducing the waste of material from excessive trimming and fitting of the pad-ding and trim material.

These and other objects of this invention will become more apparent as reference is had to the enclosed drawings and the following specification wherein:

FIGURE 1 is a view of a seat assembly, with sections cut away, showing the novel spring elements in assembled position with conventional padding and trim coverings.

FIGURE 2 is a sectional side view of the seating unit shown in FIGURE 1.

FIGURE 3 is a sectional side view of the seat cushion showing cavities of the extruded spring element filled with a resilient material to increase the support in specific areas of the seat cushion.

FIGURE 4 is a perspective view of a seat back and seat cushion, with sections cut away, utilizing the conventional seat frame, padding and trim covering with the novel reinforced extruded plastics spring elements used there- FIGURE 5 shows a portion of a modified extruded plastics seat back spring element.

FIGURE 6 shows a modified extruded plastics seat spring element, with sections broken away, showing an alternate means for attaching the element to the seat frame.

Referring now to the drawings wherein like parts are designated by the same numerals. In FIGURES 1, 2 and 3, there is shown a seating unit 10 having a seat cushion 12 and a seat back cushion 14 assembled on a seat frame 16.

Secured to the seat frame 16 by suitable means is a seat support pan 18 and a seat back support pan 20. A unitary seat support element 22 of synthetic material is secured in the seat pan and a similar seat back support element 24 is secured to the seat back pan 20. The support elements 22 and 24 could be made from an extruded plastic such as polyvinyl chloride or polyethylene but are not necessarily limited to these materials. To com- 3,270,393 Patented Sept. 6, 1966 ice plete the seat assembly, conventional foam rubber padding 26 and fabric or plastic covers 28 are used.

The seat support elements 22, 24 are designed to be manufactured by extrusion of plastics through an extrusion die to form strips of the desired cross-sectional truss design. These strips may then be cut in the seat unit lengths, properly blanked or pierced for attaching and installed in the pan or on the seat frame as a unit. The resulting spring elements will be more uniform than the conventional multiple spring construction, thus allowing closer tolerances in the manufacture of the padding and trim material. The seat support elements 22, 24 consist of an upper support member 30, a lower support member 32 and interconnecting struts 34.

The softness of the seat cushions may be controlled by the plastic used, location of the interconnecting supporting struts 34 and/ or by filling the cavities formed by the struts with resilient materials such as polyurethane foam 36, as seen in FIGURE 3. In the areas of the seat where heavier loads are expected, and a stiffer area is required for comfort, the angle at which the strut is conconnected to the support members 30, 32 may be increased until a 90 connection is achieved. As the angle of connection approaches 90, the stiffness of the supported surface will increase. The thickness of the struts 34 and/ or the support members 30, 32 may be increased or decreased to help control the seat comfort.

Another way to control the softness of the seat is to fill the cavities formed by the struts with a resilient material to increase the support in the desired areas. A further control for the softness of the seat may be accomplished by varying the basic constituents of the foam for a harder or softer foam, as is commonly done in the art.

Referring now to FIGURES 4, 5 and 6, there are shown embodiments of the present invention which are similar to the above described structure. Identical reference numerals with the sufiix a and b added to the corresponding elements will be used to identify the modified spring element structures. In these applications, the seat frames 16a and 16b are designed so that the unitary seat back support elements 24a, 24b and the seat support elements 22a, 22b may be connected directly to the seat frames 16a and 16b rather than being nested in seat pan 18, as seen in FIGURES 13. More extensive trussing is utilized in these modified structures to compensate for the support supplied by the pans 18, 20.

The modified seat back support elements 24a, 24b are attached to the seat frame 16a by tabs 38 which are bent to secure a foot portion 40 of the support elements 24a, 24b. The rear of the seat support elements 22a, 22b are modified to be secured to the frame 16a by a bolt 42, as seen in FIGURE 4, or, as seen in FIGURE 6, they may have an aperture 44 adapted to fit over a hook 46 of the frame 16b. The fronts of seat support elements 22a, 22b have a foot portion 48 having a slot 50 therein. The slot 50 is adapted to be positioned about a bolt 52 which holds the foot in position on the frame 16a and also allows a certain amount of slippage at the anchor point to permit more flexibility of the seat support elements 22a, 22b.

While the preferred embodiments of the present invention have been shown and described herein it is obvious that many structural details may be changed without departing from the spirit and scope of the following claims.

I claim:

1. A method tor making a vehicle seat cushion comprising extruding a resilient material through a die, said die being adapted to form a truss design in the extruded strip, transversely cutting the strip into desired seat width lengths, blanking the necessary openings for mounting said lengths, applying padding to the upper surface of said seat length extrusion, securing a seat cover over said extrusion and said padding, and attaching said extrusion to a seat frame by means of said mounting openmgs.

2. A method for making a vehicle seat cushion comprising extruding a resilient material through an extrusion die, said die being designed to produce a strip having an upper support member, a lower support member and interconnecting strut members forming a cross-sectional truss design, transversely cutting said strips into desired seat width lengths, blanking the necessary openings for attaching said lengths, applying padding on said upper support member, and placing a seat cover over the assembled cushion.

3. A method for making a vehicle seat cushion comprising extruding a resilient material through an extrusion die, said die being designed to produce a strip having an upper support member, a lower support member and interconnecting strut members forming a cross-sectional truss design, transversely cutting said strip into desired seat width lengths, filling one or more of the cavities formed between said struts and support members With a porous resilient material, and blanking the necessary openings for attaching said lengths.

4. A method of making a vehicle seat cushion which comprises extruding a resilient material into a one-piece multi-cellular form for providing upper and lower support members extending in a substantially smooth surface continuously from the front to the rear of said seat and for extending continuously longitudinally of the extermities of said seat in the direction of extruding, extruding integrally with the upper and lower support members spaced support struts including forward and rearward struts at the opposed edges of the extrusion, re-

spectfully, extruding a plurality of additional struts formed integrally with said upper and lower support members for controlling the stiffness of said cushion, transversely cutting the extrusion into seat length units, blanking openings for attaching said unit, and mounting said unit on a seat frame for providing a vehicle seat cushion.

5. The method as claimed in claim 4 wherein the angle between said struts and support members in the area of relative heavy loading of the seat being greater than the angle of the struts in the area Oif relatively light seat loading for providing relatively greater seat stiifness in the area of relatively heavy seat loading than that provided in the area of relatively light seat loading.

6. A method for making a vehicle seat cushion comprising extruding a resilient material through a die, said die being adapted to form a truss design in the extruded strip, transversely cutting the strip into desired seat width lengths, applying padding on the upper surface of said extrusion, placing a seat cover over the padding and extrusion, and placing said seat length extrusion padding and cover in a supporting pan for completing the seat cushion.

References Cited by the Examiner UNITED STATES PATENTS 2,748,401 6/1956 Winstead 9-21 2,983,962 5/1961 Merz et a1. 264-47 3,059,251 10/1962 Pollock 26447 X 3,222,698 12/1965 Levenson 5-361 JOHN F. CAMPBELL, Primary Examiner. ALEXANDER H. BRODMERKEL, Examiner. M. R. DOWLING, T. H. EAGER, Assistant Examiners. 

1. A METHOD FOR MAKING A VEHICLE SEATED CUSHION COMPRISING EXTRUDING A RESILIENT MATERIAL THROUGH A DIE, SAID DIE BEING ADAPTED TO FORM A TRUSS DESIGN IN THE EXTRUDED STRIP, TRANSVERSELY CUTTING THE STRIP INTO DESIRED SEAT WIDTH LENGTHS, BLANKING THE NECESSARY OPENINGS FOR MOUNTING SAID LENGTHS, APPLYING PADDING TO THE UPPER SURFACE OF SAID SEAT LENGTH EXTRUSION, SECURING A SEAT COVER OVER SAID EXTRUSION AND SAID PADDING, AND ATTACHING SAID EXTRUSION TO A SEAT FRAME BY MEANS OF SAID MOUNTING OPENINGS. 